Pyro

[pahy-roh] /ˈpaɪ roʊ/

noun, plural pyros. Informal.
1.
a pyromaniac.
1.
a combining form meaning “fire,” “heat,” “high temperature,” used in the formation of compound words:
pyrogen; pyrolusite; pyromancy.
2.
Chemistry. a combining form used in the names of inorganic acids, indicating that the acid’s water content is intermediate between that of the corresponding ortho- (more water) and meta- (least water) acids (pyroantimonic, H 4 Sb 2 O 7 , pyroarsenic, H 4 As 2 O 7 , and pyrosulfuric, H 2 S 2 O 7 , acids). The combining form is also used in the names of the salts of these acids. If the acid ends in -ic, the corresponding salt ends in -ate (pyroboric acid, H 2 B 4 O 7 , and potassium pyrobate, K 2 B 4 O 7 , or pyrosulfuric, H 2 S 2 O 7 , and pyrosulfate, N 2 S 2 O 7); if the acid ends in -ous, the corresponding salt ends in -ite (pyrophosphorous acid, H 4 P 2 O 5 , potassium pyrophosphite, K 4 P 2 O 5).
combining form
1.
denoting fire, heat, or high temperature: pyromania, pyrometer
2.
caused or obtained by fire or heat: pyroelectricity
3.
(chem)

4.
(mineralogy)

before vowels pyr-, word-forming element form meaning “fire,” from Greek pyro-, combining form of pyr (genitive pyros) “fire, funeral fire,” also symbolic of terrible things, rages, “rarely as an image of warmth and comfort” [Liddell & Scott]; see fire (n.). Pyriphlegethon, literally “fire-blazing,” was one of the rivers of Hell.

pyro- or pyr-
pref.

noun

A pyromaniac, lover of fire (1977+)